1. Field of the Disclosure
The present disclosure generally relates to the manufacture of solar cells, and more particularly to a method for reducing light-induced-degradation during the manufacturing process.
2. Description of the Related Art
Presently, solar energy is an increasingly popular energy source for promoting green energy worldwide. There has been, however, a constant problem of low light-to-electricity conversion efficiency. The efficiency of the solar cell may decrease with time, particularly under a long duration of illumination; this is called the “light-induced-degradation (LID)” effect.
Conventional methods for ameliorating the LID effect includes reducing the interstitial oxygen atoms arising in the mono-crystalline and poly-crystalline wafer during the crystal growth process by improving the quality of the silicon. Altering the dopant concentration and/or applying an external magnetic field during silicon-growing also will help. Another method is to reduce the boron atoms dopant, for example, utilizing gallium or indium instead of boron as the dopant. Still another way is to employ an n-type wafer for the solar cell with a phosphorus dopant instead of a p-type wafer with a boron dopant. These methods may ameliorate the LID effect, but will also substantially increase solar cell manufacturing costs.
Chinese Patent Publication No. CN102839415 discloses a method for solving the LID effect by applying an external magnetic field during the wafer silicon-growing step, or alternatively by using gallium instead of boron as the wafer dopant. Chinese Patent Publication No. CN102437232, also discloses a gallium dopant, and alternatively a phosphorus dopant that can reduce the LID effect.
Accordingly, there exists a need to provide a solution to solve the aforesaid problems.